570 The Water-fowl Family 



This subfamily contains in North America five genera and 

 eighteen species and subspecies ; of these four occur only irregularly, 

 and two others are chiefly confined to the southern border of the 

 United States. The geese are large birds, with long and powerful 

 wings and great powers of flight. Most of them inhabit the far North 

 in the breeding season, — the genus Dendrocygna being an exception 

 in North America, — coming at the approach of winter to the lakes 

 and bays of the United States, where they assemble in large flocks. 

 They are fine swimmers but do not dive, feeding consequently in 

 shallow water and often on the land ; they feed chiefly on grasses 

 growing either on water or land, and the flesh is therefore valuable 

 for the table. 

 Generic Types. Chen. Bill about as long as head and tapering, very 

 stout at base and higher than broad, its depth at base more than 

 half the length of culmen; the cutting edges of both mandibles 

 bevelled off, leaving an elliptical space in which the large serrations or 

 lamellae are very prominent. Nostrils in basal portion of bill. Head 

 and neck of adults white. Bill and feet pink. Four species and sub- 

 species found in North America. 



Anser. Bill not longer than head, tapering, very stout at base 

 and higher than broad, but not as high as in Chen, its depth at base 

 less than half length of culmen ; the cutting edges of mandiVjles 

 slightly bevelled, leaving serrations somewhat exposed for more than 

 half the edge. Nostrils in basal portion of the bill. Head and neck 

 never white. Bill pink and feet yellow in North American species. 

 Two species and one subspecies occur in North America, but two of 

 them are only recorded from Greenland. 



Branta. Bill shorter than head, tapering, moderately stout at 

 base; cutting edges very little, if at all, bevelled, and serrations only 

 visible at extreme base. Nostrils in middle of bill. Head and neck 

 black. Tail-coverts and crissum white. Bill and feet black. Eight 

 species and subspecies are found in North America; of these two 

 are only stragglers from Europe. 



Philade. Bill not longer than head, tapering, moderately stout, 

 the nail very large, occupying nearly one-third of maxilla, serrations 

 only visible at extreme base of maxilla. Nostrils in basal half of bill. 

 Head white. Tail-coverts and crissum grayish. Bill pinkish and feet 

 yellow. Skull with superorbital depressions. Only one species in 

 genus, an inhabitant of the Bering Sea coast of Alaska. 



Dendrocygna. Bill much longer than head, the edges nearly 

 parallel, not stouter at base. Nail prominent and decurved, serra- 



